in this study, eutrophication was investigated in lake ontario to identify the interactions among effective drivers. the complexity of such phenomenon was modeled using a system dynamics approach based on a consideration of constant and variable stoichiometric ratios. the system dynamics approach is a powerful tool for developing object-oriented models to simulate complex phenomena that involve...

The results of psychophysical studies suggest that displacement velocity may contribute significantly to the sensation of subcortical somatosensory neurons. The cortical correlates of these phenomena, however, are not known. In the present study the responses of rapidly adapting (RA) neurons in the forelimb region of cat primary somatosensory cortex (SI) to controlled displacement of skin and h...

This paper considers a linear one dimensional inverse heat conduction problem with non constant thermal diffusivity and two unknown terms in a heated bar with unit length. By using the WKB method, the heat flux at the end of boundary and initial temperature will be approximated, numerically. By choosing a suitable parameter in WKB method the ill-posedness of solution will be improved. Finally, ...

In this paper, we have studied the dynamics of two identical resistively coupled Chua’s canonical circuits and have found that it is strongly affected by initial conditions, coupling strength and the presence of coexisting attractors. Depending on the coupling variable, chaotic synchronization has been observed both numerically and experimentally. Anti-phase synchronization has also been studie...

In this paper we demonstrate connections between three seemingly unrelated concepts. 1. The discrete isoperimetric problem in the infinite binary tree with all the leaves at the same level, T∞: The n-th edge isoperimetric number δ(n) is defined to be min|S|=n,S⊂V (T∞) |(S, S)|, where (S, S) is the set of edges in the cut defined by S. 2. Signed almost binary partitions: This is the special case...

First of all, we will be using the following theorem proven in class about the recurrence relation of |s(n, k)| = S * (n, k). holds for any n, k, and defines a recurrence relation for S * (n, k). Let us define (t) n = t(t + 1)(t + 2) · · · (t + n − 1) to be the polynomial in t with roots 0, −1, −2,. .. , n − 1. Let us now define a(n, k) as follows (t) n = n k=0 a(n, k)t k. (1) We want to find a...

Scalar fields with inverse power-law effective potentials may provide a negative pressure component to the energy density of the universe today, as required by cosmological observations. In order to be cosmologically relevant today, the scalar field should have a mass mφ = O(10 −33eV), thus potentially inducing sizable violations of the equivalence principle and space-time variations of the cou...

It is expected that the inflation paradigmwould be explained within superstring/Mtheory. The theory predicts that spacetime dimension is greater than four. Since observable spacetime dimension is four, it is thought that the extra dimensions would be compactified within Planck scale. Recently, it has been pointed out that it is possible to find cosmological solutions which exhibit a transient p...

The problem of zeroing the output in an arbitrary linear discrete-time system S(A,B,C,D) with a nonvanishing transfer-function matrix is discussed and necessary conditions for output-zeroing inputs are formulated. All possible real-valued inputs and real initial conditions which produce the identically zero system response are characterized. Strictly proper and proper systems are discussed sepa...